A CORNUCOPIA OF FOOD SIGNS IN RADIOLOGY

At Arab Health 2015, Fathima Hasan Mohamed, a CT radiographer, offered listeners an exclusive look into the creative minds of radiologists and physicians.

In radiology, there are diseases which show classic radiological signs that a skilled radiologist can interpret and subsequently make a diagnosis based on the signs alone. In her speech, Fathima included some of the classic signs which are associated with food items.

Hamburger

Normally, on axial CT, the vertebral facet (apophyseal) joint space resembles a hamburger.

If the facet joint is dislocated, it becomes naked or uncovered, referred to as “naked facet sign.” This sign is characteristic of a flexion­distraction injury and indicates severe ligamentous disruption and spinal instability.

Sausage digits

Refers to the clinical and radiological appearance of diffuse fusiform swelling of digits as a result of soft­tissue inflammation from underlying arthritis or dactylitis. The most common cause is psoriatic arthropathy. Other causes include osteomyelitis, sickle cell anemia, sarcoidosis, and tuberculous dactylitis (spina ventosa), syphilitic dactylitis and leukemia.

Apple core lesion

Focal circumferential thickening of the bowel wall and narrowing of colonic lumen seen in annular colorectal carcinomas resembles a partially eaten apple.

Berry aneurysm

On CT, intracranial saccular aneurysms may resemble a berry. They are congenital and usually occur where arteries bifurcate. They may occur in isolation or in association with polycystic kidneys or aortic coarctation.

Banana

Seen at antenatal US, refers to the abnormal appearance of the cerebellum. The cerebellum has a banana shape because it is wrapped around the posterior brainstem due to downward traction of the spinal cord

Lemon

Seen at antenatal US, refers to the abnormal appearance of the cerebellum. It is associated with neural tube defects and is most often seen in cases of open spina bifida. An abnormally shaped fetal head on a second­trimester scan performed can resemble a lemon in the axial cross section because the frontal bones are flattened or concave.

Celery stalk metaphysis

Refers to vertical striations in the metaphysiы of long bones or pelvis indicative of dysplastic bone diseases like osteopathia striata. It can also be seen in congenital rubella infection.

Onion skin periosteal reaction

Refers to the formation of concentric layers of bone, giving a lamellated or onion skin appearance. It occurs as a reaction to acute osteomyelitis, Ewing’s sarcoma and osteosarcoma

Coffee bean

This characteristic sign of sigmoid volvulus can be seen on abdominal radiography. It presents as a twisted air­filled loop of sigmoid colon that projects up and away from the pelvis. The two apposed medial walls of the dilated bowel resembling the cleft of a coffee bean.

Eggshell calcification

Shell like calcification of the walls of hilar, and in some cases, mediastinal, cervical and intraperitoneal lymph nodes. Calcification occurs in the periphery of the nodes.

It is seen in cases of sarcoidosis, silicosis, following treatment of lymphoma, pneumoconiosis, advanced pulmonary disease, scleroderma and amyloidosis.

Honeycomb lung

Is seen in advanced stages of fibrosis in which healthy lung tissue is replaced by coarse reticular interstitial areas of increased opacity and cystic spaces. Common causes of honeycomb lung include pneumoconiosis, sarcoidosis, fibrosing alveolitis, eosinophilic granuloma, cystic bronchiectasis and rheumatoid diseases.

Linguine

Is seen in cases of intracapsular rupture of gel and silicone breast implants. It is characterized by fine wavy lines of low signal intensity within the ruptured implant. It is best visualized on T2 weighted MR images.

Donut

1) Circumferential thickening of the bowel wall seen in cases of colon carcinoma, inflammatory bowel disease and intussusceptions.

2) The donut sign may also be observed at scintigraphy in subacute testicular torsion. Preserved dartos perfusion creates a halo, or donut shaped area.

Licked candy stick appearance

Refers to the tapering of the tips of the metacarpal and metatarsal bones, phalanges or clavicles. It is most commonly associated with psoriatic arthropathy, leprosy and rheumatoid arthritis.

Cottage loaf

MRI appearance of the partially herniated liver through the ruptured right hemidiaphragm. It can resemble a traditional bread baked in England.

"It may sound a little silly, but the radiology literature is replete with signs, some more fanciful than others," she concluded, before receiving an enthusiastic round of applause.

Images, cases courtesy of Dr. Mohammad Taghi Niknojad, Dr. Frank Guillard, Dr. Maulik S. Pate. Radiopaedia.org